Liquid crystal display device

ABSTRACT

Pixel regions are formed on a liquid-crystal-side surface of one substrate out of respective substrates which are arranged to face each other in an opposed manner with liquid crystal therebetween, wherein each pixel region includes pixel electrodes having bent portions and counter electrodes which are arranged at positions where the pixel electrodes are shifted in parallel, the pixel electrode and the counter electrode are respectively constituted of two electrodes which are overlapped to each other as an upper layer and a lower layer by way of an insulation film, and to the lower-layer side electrode of at least one electrode out of the pixel electrode and the counter electrode, projections which further project from crests of convex-portion sides of the bent portions and extend toward another electrode side are provided.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a liquid crystal display device,and more particularly to a liquid crystal display device of high qualitywhich enhances display quality by enhancing the numerical aperture andsuppressing regions where a domain occurs.

[0003] 2. Description of the Related Art

[0004] A so-called lateral electric field type (IPS type) liquid crystaldisplay device is constituted such that on each pixel region formed on aliquid crystal side surface of one of substrates which are arranged toface each other with liquid crystal sandwiched therebetween, a pixelelectrode and a counter electrode which generates an electric fieldbetween the pixel electrode and the counter electrode are formed, andliquid crystal is activated by components of the electric fieldincluding parallel to the substrate.

[0005] In the active matrix type liquid crystal display device to whichsuch a structure is applied, first of all, on the liquid crystal sidesurface of one substrate, respective regions which are surrounded by aplurality of juxtaposed gate signal lines and a plurality of juxtaposeddrain signal lines which cross these gate signal lines constitute pixelregions.

[0006] Then, each pixel region includes a thin film transistor which isoperated in response to a scanning signal from the gate signal line, thepixel electrode to which a video signal is supplied from a drain signalline through the thin film transistor, and the counter electrode towhich a signal which becomes reference with respect to the video signalis supplied.

[0007] Here, the pixel electrode and the counter electrode are formed ina strip-like pattern which extends in one direction, wherein therespective electrodes are usually constituted of two or more electrodesand are alternately arranged.

[0008] Further, in such a constitution, following type of liquid crystaldisplay device is known, that is the counter electrodes are formed on anupper surface of an insulation film formed to cover also the drainsignal lines and, at the same time, the counter electrodes are formedalong the drain signal lines such that the counter electrodes have thecenter axes thereof substantially aligned with the drain signal linesand have a width larger than a width of the drain signal lines. This isbecause those lines of electric force from the drain signal lines can beeasily terminated at the counter electrodes disposed above the drainsignal lines and it is possible to prevent the lines of electric forcesfrom being terminated to the pixel electrodes. That is, when lines ofelectric forces are terminated at the pixel electrodes, this gives riseto noises.

[0009] Then, the respective counter electrodes are formed integrallywith counter voltage signal lines formed on an upper surface of theinsulation film on the same layer and reference signals are supplied torespective counter electrodes through these counter voltage signallines.

[0010] Further, there has been known a liquid crystal display devicewhich adopts a so-called multi-domain system in which the pixelelectrodes and the counter electrodes which are alternately arranged areformed in a pattern in which these electrodes have a large L-shaped bentportion.

[0011] With respect to liquid crystal, even when the moleculararrangement is at the same state, the polarized state of transmittinglight is changed in response to the incident direction of light which isincident on a liquid crystal display panel and hence, opticaltransmissivity differs corresponding to the incident direction of light.

[0012] Such viewing-angle dependency of the liquid crystal display panelinduces a luminance inversion phenomenon when a viewing point isobliquely inclined with respect to a viewing angle direction and hence,the liquid crystal display panel exhibits display characteristics thatimages are colored in a case of color display.

[0013] Accordingly, the pixel electrode is formed in a pattern in whichat least one bent portion is formed in the extending direction and thecounter electrode is formed in a shape which shifts this pattern inparallel, and using an imaginary line which connects bent points ofthese respective electrodes as a boundary, the direction of an electricfield acting between respective electrodes differ between one region andthe other region whereby coloring of images dependent on the viewingangle is compensated.

SUMMARY OF THE INVENTION

[0014] However, with respect to the liquid crystal display device havingsuch a constitution, in a design pattern of electrodes having “theL-shaped” bent portions, when etching is performed during the formationof electrodes, concave/convex portions of the bent portions becomesmooth or rounded and are formed into a shape close to a straight line.When this occurs, a domain region (a region which is also referred to asa discrimination region in which a portion which has the electric fielddirection different from the normal electric field direction is formedand hence, display is not performed normally) spreads. Further, beinginfluenced by irregularities of etching conditions, this tendency ischanged. Such a tendency becomes more apparent with the use of atransparent conductive film made of ITO (Indium Tin Oxide), ITZO (IndiumTin Zinc Oxide) as a material of the counter electrodes.

[0015] Further, it has been known that when a so-called NB (normallyblack) display is adopted, the domain region is displayed dark even whenthis portion is subjected to bright display thus giving rise todifference with respect to desired luminance to be displayed.Particularly, with respect to the high-definition pixels of 200 ppiclass, it is needless to say that the adverse influence which thisregion occupying an opening portion of one pixel gives to the displaycharacteristics cannot be ignored.

[0016] For example, even when the pixel seems to display the normalluminance value, due to the influence of the domain region, the pixel isrecognized as a pixel with darkened luminance. Further, this differenceis changed in a finish pattern thus causing luminance irregularitieswithin a screen. Further, the occurrence of this domain also becomes acause for giving an adverse influence that a rising response speed ofliquid crystal molecule is lowered.

[0017] Further, although the large enhancement of numerical aperture canbe expected in the liquid crystal display system, as a by product, it isnecessary to overlap the counter electrode (transparent conduct film)having a width about 3 times as large as a width of the drain signalline by way of a protective film formed of an organic material layer andhence, particularly with respect to the high-definition pixels of about200 ppi, a sufficient electrode interval cannot be insured.

[0018] For example, when the drain signal line having a width of 6 μm isused, it is necessary to cover the drain signal line with the counterelectrode having a width of 18 μm. That is, when the width of thecounter electrode is narrowed, electric-field noises from the drainsignal line intrudes into the liquid crystal layer between the pixelelectrode and the counter electrode and hence, the normal luminancecurve is changed in response to signals from the drain signal linewhereby a so-called smear phenomenon that the luminance curve is changedis observed. Accordingly, although efforts have been made to relativelynarrow the drain signal line to 4-5 μn, with respect to a large-sizedpanel, there arises a drawback that disconnection of the drain signallines frequently occurs.

[0019] Further, in such type liquid crystal display device, it may bepossible to integrally form the counter voltage signal line whichsupplies a voltage to the counter electrode and the counter electrode.However, when the counter voltage signal line is arranged at the centerof pixel region, it is necessary to arrange a through hole formed in anorganic protective film PAS at the center portion of the screen. In thiscase, the disturbance of orientation or the disturbance of electricfield is generated in this portion thus giving rise to a drawback thatthe contrast is lowered and the numerical aperture is lowered in theblack display.

[0020] The present invention has been made under such circumstances andit is an advantage of the present invention to provide a liquid crystaldisplay device which can enhance display quality by enhancing numericalaperture and by suppressing the occurrence of domains.

[0021] Here, designing of bent portions of comb-teeth electrodes isdisclosed in Japanese Patent Laid open 2002-40456 and Japanese PatentLaid Open 2000-56320, for example.

[0022] The advantage, other advantages and novel features of the presentinvention will become apparent from the description of thisspecification and attached drawings.

[0023] To briefly explain the summary of typical inventions among theinventions disclosed in this specification, they are as follows.

[0024] (1) The liquid crystal display device according to the presentinvention is, for example, characterized in that on each pixel regionformed on a liquid-crystal-side surface of one substrate out ofrespective substrates which are arranged to face each other in anopposed manner with liquid crystal therebetween, a pixel electrodehaving a bent portion and a counter electrode which is arranged at aposition where the pixel electrode is shifted in parallel are formed, atleast one electrode out of the pixel electrode and the counter electrodeis constituted of two electrodes which are superposed as an upper layerand a lower layer by way of an insulation film, and a projection whichis further projected from a crest of a convex-side portion of the bentportion toward another electrode side is formed on the lower-layer-sideelectrode out of two electrodes.

[0025] (2) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (1), in the lower-layer-side electrode of the anotherelectrode, a notched portion which further cuts off a bottom portion ofa concave-portion side of the bent portion is formed.

[0026] (3) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (1), an insulation film interposed between two pixelelectrodes and an insulation film interposed between two counterelectrodes differ in the number of lamination.

[0027] (4) The liquid crystal display device according to the presentinvention is, for example, characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, regions which are surrounded by aplurality of juxtaposed gate signal lines and a plurality of juxtaposeddrain signal lines which cross these gate signal lines are formed aspixel regions, a thin film transistor driven in response to a scanningsignal from the gate signal line and a pixel electrode to which a videosignal is supplied from the drain signal line through a drain electrodeand a source electrode of the thin film transistor are provided to theinside of each pixel region, the drain signal line is formed in a zigzagshape having bent portions at a portions where the drain signal linecrosses the gate signal line and at least at a substantially centerportion of the pixel region, the thin film transistor is formed in thevicinity of the concave-portion side of the bent portion of the drainsignal line, the drain electrode is formed of a portion of the drainsignal line, and the source electrode is formed so as to face the drainelectrode in an opposed manner with a channel length in the runningdirection of the gate signal line.

[0028] (5) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (4), the source electrode of the thin film transistor isconnected to the pixel electrode, and the vicinity of the connectingportion of the pixel electrode with the source electrode includes anextension having a pattern which reduces a domain between the pixelelectrode and the counter electrode and blocks electric field noisesfrom the gate signal line by shielding.

[0029] (6) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (4), the thin film transistor is arranged betweenextensions of the pixel electrode and the counter electrode which arearranged close to each other.

[0030] (7) The liquid crystal display device according to the presentinvention is, for example, characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, regions which are surrounded by aplurality of juxtaposed gate signal lines and a plurality of juxtaposeddrain signal lines which cross these gate signal lines are formed aspixel regions, a thin film transistor driven in response to a scanningsignal from the gate signal line and a pixel electrode to which ascanning signal is supplied from the drain signal line through a drainelectrode and a source electrode of the thin film transistor areprovided to the inside of each pixel region, the drain signal line isformed in a zigzag shape having bent portions at portions where thedrain signal line crosses the gate signal line and at least at asubstantially center portion of the pixel region, the thin filmtransistor is formed in a pattern in which a side of the drain electrodewhich faces the source electrode in an opposed manner has a concaveportion and also in a pattern in which a side of the source electrodewhich faces the drain electrode in an opposed manner has a convexportion.

[0031] (8) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (7), the drain electrode of the thin film transistor usesthe pattern of the bent portion of the drain signal line as it is.

[0032] (9) The liquid crystal display device according to the presentinvention is, for example, characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, pixel regions which are surrounded bya plurality of juxtaposed gate signal lines and a plurality ofjuxtaposed drain signal lines which cross these gate signal lines areformed, on each pixel region, a switching element which is driven inresponse to a scanning signal from the gate signal line, a pixelelectrode to which a video signal is supplied from the drain signal linethrough the switching element, and a counter electrode which isconnected to a counter voltage signal line and generates an electricfield between the pixel electrode and the counter electrode are formed,the counter electrode includes a lower-layer counter electrode and anupper-layer counter electrode which is formed above the lower-layercounter electrode, the lower-layer counter electrode is formed such thatthe lower-layer counter electrodes are respectively arranged at bothsides of the drain signal line through the drain signal line and a firstinsulation film, and the upper-layer counter electrode is formed suchthat the upper-layer counter electrode covers the drain signal line andthe lower-layer counter electrodes by way of the second insulation film.

[0033] (10) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (9), the drain signal line and the lower-layer counterelectrodes which are arranged at both sides of the drain signal linehave bent portions and, at the same time, projections which are furtherprojected from crests at convex-sides of the bent portions of thelower-layer counter electrodes and are extended to the pixel electrodeside are formed.

[0034] (11) The liquid crystal display device according to the presentinvention is, for example, characterized in that on each pixel regionformed on a liquid-crystals-side surface of one substrate out ofrespective substrates which are arranged to face each other with liquidcrystal therebetween, a pixel electrode having a bent portion and acounter electrode which is arranged at a position where the pixelelectrode is shifted in parallel, and a projection which is projectedfrom a crest of the convex-portion side of the bent portion of oneelectrode out of the pixel electrode and the counter electrode toward abottom portion of the concave-portion side of the bent portion ofanother electrode which faces one electrode in an opposed manner areformed, and the bottom portion of the concave-portion side of the bentportion of the another electrode is notched to form a notched portion.

[0035] (12) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (9), the respective lower-layer counter electrodes whichare arranged at both sides of the drain signal line are connected toeach other by a connector which is arranged to cross the drain signalline.

[0036] (13) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (9) or (12), the lower-layer counter electrodes are bentaway from each other such that the lower-layer counter electrodes arenot overlapped to the drain signal line at a side of the gate signalline.

[0037] (14) The liquid crystal display device according to the presentinvention is, for example, characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, pixel regions which are surrounded bya plurality of juxtaposed gate signal lines and a plurality ofjuxtaposed drain signal lines which cross these gate signal lines areformed, on each pixel region, a switching element which is driven inresponse to a scanning signal from the gate signal line, a pixelelectrode to which a video signal is supplied from the drain signal linethrough the switching element, and a counter electrode which isconnected to a counter voltage signal line and generates an electricfield between the pixel electrode and the counter electrode are formed,the counter electrode includes a lower-layer counter electrode and anupper-layer counter electrode which is formed above the lower-layercounter electrode, the lower-layer counter electrode is formed such thatlower-layer counter electrode is constituted of an intermediateconductive layer between the drain signal line and the gate signal line,is insulated from the drain signal line by way of a first insulationfilm and is insulated from the gate signal line by way of a thirdinsulation film, is arranged in the vicinity of at least one signal lineout of the drain signal line and the gate signal line, and is extendedin the extending direction of the drain signal line.

[0038] (15) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (14), the lower-layer counter electrode constitutes anoverlapped region together with the pixel electrode by way of the firstinsulation film and forms a holding capacitance in the region.

[0039] (16) The liquid crystal display device according to the presentinvention is, for example, characterized in that on the premise of theconstitution (14) or (15), the upper-layer counter electrode andlower-layer counter electrode are electrically connected to each otherover the gate signal line within the pixel region via a through hole.

[0040] (17) The liquid crystal display device according to the presentinvention is, for example, characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, pixel regions which are surrounded bya plurality of juxtaposed gate signal lines and a plurality ofjuxtaposed drain signal lines which cross these gate signal lines areformed, on another substrate, color filters having bent portions areformed within the pixel region, and projections which are furtherprojected from crests of convex-portion sides of the bent portions areformed or notched portions are formed at the concave-portion sides ofthe bent portions.

[0041] Here, the present invention is not limited to the constitutionand various modification can be conceived without departing from thetechnical concept of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0042]FIG. 1 is a constitutional view showing one embodiment of a pixelof a liquid crystal display device according to the present invention.

[0043]FIG. 2 is a plan view showing another embodiment of a pixel of aliquid crystal display device according to the present invention.

[0044]FIG. 3 is a plan view showing another embodiment of a pixel of aliquid crystal display device according to the present invention.

[0045]FIG. 4 is a plan view showing one embodiment of pixel electrodesand counter electrodes of a liquid crystal display device according tothe present invention.

[0046]FIG. 5 is an explanatory view for explaining the distribution ofan electric field between a pixel electrode and a counter electrode of aliquid crystal display device according to the present invention.

[0047]FIG. 6 is a plan view showing another embodiment of pixelelectrodes and counter electrodes of a liquid crystal display deviceaccording to the present invention.

[0048]FIG. 7 is a plan view for explaining a pattern of a pair ofelectrodes which generates an electric field of the liquid crystaldisplay device according to the present invention.

[0049]FIG. 8 is a plan view showing one embodiment of a thin filmtransistor of a liquid crystal display device of the present invention.

[0050]FIG. 9 is a comparison view for showing an advantageous effect ofa thin film transistor of a liquid crystal display device of the presentinvention.

[0051]FIG. 10 is an explanatory view for exhibiting advantageous effectsof a liquid crystal display device according to the present invention.

[0052]FIG. 11 is a plan view showing another embodiment of a thin filmtransistor of a liquid crystal display device of the present invention.

[0053]FIG. 12 is an explanatory view for explaining advantageous effectsof a thin film transistor of a liquid crystal display device accordingto the present invention.

[0054]FIG. 13 is a plan view for showing one embodiment of theconstitution of drain signal lines and the vicinity of the drain signallines of a liquid crystal display device according to the presentinvention.

[0055]FIG. 14 is across-sectional view taken a long a line XIV-XIV inFIG. 13.

[0056]FIG. 15 is a plan view showing another embodiment of a pixel of aliquid crystal display device according to the present invention.

[0057]FIG. 16 is across-sectional view taken along a line XVI-XVI inFIG. 15.

[0058]FIG. 17 is a plan view showing the first step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0059]FIG. 18 is a plan view showing the second step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0060]FIG. 19 is a plan view showing the third step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0061]FIG. 20 is a plan view showing the fourth step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0062]FIG. 21 is a plan view showing the fifth step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0063]FIG. 22 is a plan view showing the sixth step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0064]FIG. 23 is a plan view showing the seventh step out of steps forshowing one embodiment of a manufacturing method of a liquid crystaldisplay device according to the present invention.

[0065]FIG. 24 is a plan view showing one embodiment of the whole of aliquid crystal display device according to the present invention.

[0066]FIG. 25 is a plan view showing another embodiment of respectivebent portions of a pixel electrode and a counter electrode of a liquidcrystal display device according to the present invention.

[0067]FIG. 26 is a graph showing an advantageous effect derived from theconstitution of an electrode shown in FIG. 25.

[0068]FIG. 27 is a constitutional view for showing another embodiment ofa pixel of a liquid crystal display device according to the presentinvention.

[0069]FIG. 28 is a constitutional view for showing another embodiment ofa pixel of a liquid crystal display device according to the presentinvention.

[0070]FIG. 29 is a constitutional view for showing another embodiment ofa pixel of a liquid crystal display device according to the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0071] Preferred embodiments of the present invention are explainedhereinafter in conjunction with attached drawings.

[0072] Embodiment 1.

[0073] <<Whole Constitution>>

[0074]FIG. 24 is a plan view showing one embodiment of the constitutionof the whole liquid crystal display device according to the presentinvention. The drawing is drawn corresponding to an actual geometricarrangement although a portion thereof is depicted as an equivalentcircuit.

[0075] In the drawing, there are provided a pair of transparentsubstrates SUB1, SUB2 which are arranged to face each other in anopposed manner with liquid crystal therebetween. The liquid crystal isfilled and sealed in a space defined between these substrates SUB1, SUB2using a sealing material SL which also has a function of fixing anothertransparent substrate SUB2 to one transparent substrate SUB1.

[0076] On a liquid-crystal-side surface of one transparent substrateSUB1 which is surrounded by the sealing material SL, a plurality of gatesignal lines GL which extend in the x direction and are juxtaposed inthe y direction and a plurality of drain signal lines DL which extend inthe y direction and are juxtaposed in the x direction are formed.

[0077] Respective regions surrounded by respective gate signal lines GLand respective drain signal lines DL constitute pixel regions and, atthe same time, a mass of these respective pixel regions in a matrixarray constitute a liquid crystal display part AR.

[0078] In respective pixel regions which are juxtaposed in the xdirection, a common counter voltage signal line CL which runs withinrespective pixel regions is formed. The counter voltage signal line CLconstitutes a signal line which supplies a voltage which becomes thereference with respect to video signals to counter electrodes CT ofrespective pixel regions which will be explained later.

[0079] Each pixel region includes a thin film transistor TFT which isoperated in response to a scanning signal supplied from one-side gatesignal line GL and a pixel electrode PX to which the video signals aresupplied from the one-side drain signal line DL through the thin filmtransistor TFT.

[0080] The pixel electrode PX generates an electric field between thepixel electrode PX and the counter electrode CT connected to the countervoltage signal line CL and optical transmissivity of the liquid crystalis controlled in response to the electric field.

[0081] Respective ends of the gate signal line GL extend over thesealing material SL and extended ends of the gate signal line GLconstitute terminals GLT to which output terminals of a scanning signaldrive circuit V are connected. Further, input terminals of the scanningsignal drive circuit V are configured such that signals supplied from aprinted circuit board (not shown in the drawing) which is arrangedoutside a liquid crystal display panel are inputted thereto.

[0082] The scanning signal drive circuit V is constituted of a pluralityof semiconductor devices, wherein a plurality of neighboring gate signallines GL which are arranged close to each other are formed into a groupand one semiconductor device is allocated to each group.

[0083] In the same manner, respective one ends of the drain signal linesDL extend over the sealing material SL and the extending ends of thedrain signal line DL constitute terminals DLT to which output terminalsof a vide signal drive circuit He are connected. Further, inputterminals of the video signal drive circuit He are configured such thatsignals supplied from a printed circuit board (not shown in the drawing)which is arranged outside a liquid crystal display panel are inputtedthereto.

[0084] The video signal drive circuit He is also constituted of aplurality of semiconductor devices, wherein a plurality of neighboringdrain signal lines DL which are arranged close to each other are formedinto a group and one semiconductor device is allocated to each group.

[0085] Further, the counter voltage signal lines have right-side endportions thereof in the drawing connected in common and a connectionline thereof extends over the sealing material SL and an extended endconstitutes a terminal CLT. A voltage which becomes the reference withrespect to the video signal is supplied from these terminals.

[0086] With respect to respective gate signal lines GL, in response to ascanning signal from the scanning signal drive circuit V, one of them issequentially selected.

[0087] Further, to respective drain signal lines DL, a video signal issupplied from the video signal drive circuit He at the timing ofselecting the gate signal lines GL.

[0088] Here, in the above-mentioned embodiment, although the scanningsignal drive circuit V and the video signal drive circuit He areindicated as semiconductor devices mounted on the transparent substrateSUB1, tape carrier type semiconductor devices which are connectedastride the transparent substrate SUB1 and a printed circuit board maybe used. Further, when a semiconductor layer of the thin film transistorTFT is made of polycrystalline silicone (p-Si), the semiconductorelement made of polycrystalline silicon may be formed on the transparentsubstrate SUB1 together with a wiring layer.

[0089] <<Constitution of Pixel>>

[0090]FIG. 1 is a view showing one embodiment of the specificconstitution of the pixel, wherein FIG. 1A is a plan view, FIG. 1B is across-sectional view taken along a line b-b in FIG. 1A, and FIG. 1C is across-sectional view taken along a line c-c in FIG. 1A.

[0091] On the liquid-crystal-side surface of the transparent substrateSUB1, first of all, a pair of gate signal lines GL which extend in the xdirection and are juxtaposed in the y direction are formed.

[0092] These gate signal lines GL surround a rectangular region togetherwith a pair of drain signal lines DL described later and this region isconfigured to constitute the pixel region.

[0093] Further, in portions within the pixel region which are close tothe gate signal lines GL, the counter voltage signal lines CL are formedin parallel to the gate signal line GL and these counter voltage signallines CL are formed such that each counter voltage signal line CL runsinside respective pixel regions which are juxtaposed in the x directionin the drawing.

[0094] Over the surface of the transparent substrate SUB1 on which thegate signal lines GL and the counter voltage signal lines CL are formed,an insulation film GI (see FIGS. 1B, C) made of SiN, for example, isformed such that the insulation film GI also covers the gate signallines GL and the counter voltage signal lines CL.

[0095] The insulation film GI is configured to perform a function as aninterlayer insulation film with respect to the gate signal lines GL inregions where the drain signal lines DL described later are formed and afunction as a gate insulation film in regions where the thin filmtransistors TFT described later are formed.

[0096] Then, over the surface of the insulation film GI, semiconductorlayers AS made of amorphous Si, for example, are formed such that eachsemiconductor layer AS is overlapped to a portion of the gate signalline GL.

[0097] This semiconductor layer AS is a semiconductor layer of the thinfilm transistor TFT, wherein by forming a drain electrode SD1 and asource electrode SD2 over the semiconductor layer AS, it is possible toconstitute an MIS type transistor structure having an inversed staggeredstructure which uses a portion of the gate signal line GL as the gateelectrode.

[0098] Here, the drain electrode SD1 and the source electrode SD2 aresimultaneously formed at the time of forming the drain signal lines DL.

[0099] That is, the drain signal lines DL which extend in the ydirection and are juxtaposed in the x direction are formed, the portionof the drain signal line DL is extended over an upper surface of thesemiconductor layer AS so as to form the drain electrode SD1, and thesource electrode SD2 is formed in a spaced apart manner by a length ofchannel of the thin film transistor TFT from the drain electrode SD1.

[0100] Further, the source electrode SD2 is integrally formed with alower-layer pixel electrode PXM which is formed within the pixel region.Here, the lower-layer pixel electrode PXM is arranged to be partiallyoverlapped to the upper-layer pixel electrode PX described later andhence is expressed in a distinguished manner from the upper-layer pixelelectrode PX.

[0101] That is, the lower-layer pixel electrode PXM is constituted of agroup consisting of a plurality of electrodes (two in the drawing) whichextend in the y direction and are juxtaposed in the x direction withinthe pixel region. One end portion of one of these lower-layer pixelelectrodes PXM also functions as the source electrode SD2 and anotherend portion of one of these lower-layer pixel electrodes PXM iselectrically connected with a corresponding portion of anotherlower-layer pixel electrodes PXM.

[0102] Further, the lower-layer pixel electrodes PXM are formed in azigzag shape in the y direction in the drawing together with theupper-layer pixel electrodes PX and the counter electrodes CT describedlater thus forming the constitution which adopts a so-calledmulti-domain system.

[0103] For example, in FIG. 1A, each lower-layer pixel electrode PXMincludes three bent portions, and on the respective bent portions,respective projections CP which are further projected fromconvex-portion side crests of the respective bent portions areintegrally formed with the lower-layer pixel electrode PXM, for example.The manner of operation or the function of these projections CP areexplained later.

[0104] Here, although not shown in the drawing, thin layers which aredoped with impurities of high concentration are formed on interfacesbetween the semiconductor layer AS and the drain electrode SD2 and thesource electrode SD2 and these layers function as contact layers.

[0105] With respect to these contact layers, at the time of forming thesemiconductor layer AS, for example, impurity layers of highconcentration are already formed on surfaces thereof. Accordingly, usinga pattern of the drain electrode SD1 and the source electrode SD2 formedon an upper surface of the semiconductor layer AS as a mask, the contactlayers can be formed by etching the impurity layers which are exposedfrom the pattern.

[0106] On the surface of the transparent substrate SUB1 on which thethin film transistors TFT, the drain signal lines DL, the drainelectrodes SD1, the source electrodes SD2 and the lower-layer pixelelectrodes PXM are formed, a protective film PAS is formed. Theprotective film PAS is served for obviating the direct contact of thethin film transistors TFT with the liquid crystal and is configured toprevent the degradation of characteristics of the thin film transistorsTFT.

[0107] Here, the protective film PAS is constituted of a sequentiallaminated body consisting of an inorganic material layer made of amaterial such as SiN and an organic material layer made of a materialsuch as resin or is constituted of only an organic material layer asshown in FIG. 1B or FIG. 1C. At least the organic material layer is usedas the protective film PAS for reducing the dielectric constant of theprotective film.

[0108] On an upper surface of the protective film PSV, the upper-layerpixel electrode PX, the counter electrode CT and the counter voltagesignal line CLt are respectively formed. All of the upper-layer pixelelectrode PX, the counter electrode CT and the counter voltage signalline CLt are formed of a light-transmitting conductive film made of ITO(indium tin oxide), ITZO (indium tin zinc oxide), IZO (indium zincoxide), SnO₂ (tin oxide), In₂O₃ (indium oxide). This provision is madeto enhance the so-called numerical aperture of the pixel.

[0109] First of all, each upper-layer pixel electrode PX is formed in anoverlapped manner on the lower-layer pixel electrode PXM except for bothend portions thereof. One end portion (an upper-side end portion in thedrawing) of the upper-layer pixel electrode PX is connected to aconnecting portion of each lower-layer pixel electrode PXM via throughholes TH1, TH2 which are formed in the protective film PAS. Due to sucha constitution, the lower-layer pixel electrodes PXM and the upper-layerpixel electrodes PX are always held at the equal potential.

[0110] In this case, each upper-layer pixel electrode PX is arrangedsuch that a center axis thereof in the running direction issubstantially aligned with the lower-layer pixel electrode PXM and has awidth larger than a width of the lower-layer pixel electrode PXM.

[0111] Here, in this case, the projection CP which is formed on thelower-layer pixel electrode PXM is preliminarily formed such that theprojection CP extends from the lower-layer pixel electrode PXM to anextent that the projection CP is sufficiently projected from theupper-layer pixel electrode PX.

[0112] Here, the projection CP formed in the lower-layer pixel electrodePXM is not formed on the upper-layer pixel electrode PX. That is,although the projection CP is formed on the lower-layer pixel electrodePXM, the projection CP is not formed on the upper-layer pixel electrodePX.

[0113] Further, the counter electrode CT is constituted of a group ofelectrodes consisting of a plurality of (three in the drawing)electrodes which extend in the y direction and are juxtaposed in the xdirection in the same manner as the upper-layer pixel electrodes PX.Respective counter electrodes CT are arranged such that they are formedin a zigzag shape in the running direction and are in parallel with theabove-mentioned upper-layer pixel electrodes PX.

[0114] Still further, each counter electrode CT is, when viewed in plan,positioned between the upper-layer pixel electrodes PX.

[0115] That is, the counter electrodes CT and the upper-layer pixelelectrodes PX are arranged in order of the counter electrode CT, theupper-layer pixel electrode PX, the counter electrode CT, theupper-layer pixel electrode PX, . . . , the counter electrode CT fromthe one-side drain signal line DL to another-side drain signal line DLat an equal interval respectively.

[0116] Here, the counter electrodes CT which are positioned at bothsides of the pixel region are formed such that the counter electrodes CTare overlapped to the drain signal lines DL. Due to such a constitution,the drain signal lines DL are formed in a zigzag shape in conformitywith the pattern of the counter electrodes CT. Further, the counterelectrodes CT are formed in common with the corresponding counterelectrodes CT of other pixel regions which are disposed close to eachother in the x direction.

[0117] That is, the counter electrode CT is overlapped to the drainsignal line DL such that a center axis of the counter electrode CT issubstantially aligned with a center axis of the drain signal line DL,and a width of the counter electrode CT is set larger than a width ofthe drain signal line DL. The left-side counter electrode CT which isprojected with respect to the drain signal line DL constitutes one ofrespective counter electrodes CT of the left-side pixel region, whilethe right-side counter electrode CT which is projected with respect tothe drain signal line DL constitutes one of respective counterelectrodes CT in the right-side pixel region.

[0118] In this manner, by forming the counter electrode CT having thewidth larger than the width of the drain signal line DL above the drainsignal line DL, it is possible to obtain an advantageous effect thatlines of electric forces from the drain signal line DL are terminated tothe counter electrodes CT while obviating the termination of the linesof electric forces to the upper-layer pixel electrodes PX (and thelower-layer pixel electrodes PXM). When lines of electric force from thedrain signal lines DL are terminated to the upper-layer pixel electrodesPX (and the lower-layer pixel electrodes PXM), this gives rise tonoises.

[0119] Further, respective counter electrodes CT which are formed of agroup of electrodes are integrally formed with the counter voltagesignal lines CLt which are formed of the same material as the counterelectrodes CT and are formed to sufficiently cover the gate signal linesGL. The counter voltage signal lines CLt are electrically connected tothe previously-mentioned counter voltage signal lines CL to each otherin regions not shown in the drawing.

[0120] The reason that the counter voltage signal lines CL are providedseparately from the counter voltage signal lines CLt lies in that sincethe counter voltage signal lines CLt are made of a material having largeresistance, with the provision of the counter voltage signal line CLhaving small resistance, the overall resistance can be reduced.

[0121] Below the counter voltage signal lines CL, CLt or the counterelectrodes CT, the source electrodes SD2 of the thin film transistorsTFT or the pixel electrodes PX are positioned. Due to such aconstitution, a capacitive element Cstg which uses a gate insulationfilm GI as a dielectric film is formed between the pixel electrode PXand the counter voltage signal line CL.

[0122] This capacitive element Cstg is configured to have a function ofstoring video signals supplied to the pixel electrode PX, for example,for a relatively long period.

[0123] Then, over the upper surface of the transparent substrate SUB1 onwhich the upper-layer pixel electrodes PX, the counter electrodes CT andthe counter voltage signal lines CLt are formed in this manner, anorientation film (not shown in the drawing) is formed such that theorientation film also covers these components. The orientation film is afilm which is directly brought into contact with the liquid crystal anddetermines the initial orientation direction of molecules of the liquidcrystal by rubbing which is applied to a surface thereof.

[0124] <<Observation>>

[0125] The pixel electrodes PX, PXM and the counter electrodes CT havingthe above-mentioned constitution are configured to solve the followingrespective drawbacks with the use of projections CP formed on thelower-layer pixel electrodes PXM. That is, the above-mentionedelectrodes PX, PXM and CT can solve the drawbacks that these bentportions, compared to portions between other pixel electrodes PX, PXMand the counter electrodes CT, exhibit the larger distance and thedirection of an electric field is changed whereby a delay of responsespeed occurs or domains are generated.

[0126] Here, the reason that the projections CP are formed on the pixelelectrode PXM is to prevent a phenomenon that since the pixel electrodePXM is formed of a layer different from a layer of the counterelectrodes CT, the distance between the projection CP and the counterelectrode CT becomes close to each other thus an electricshort-circuiting is liable to be easily generated.

[0127] However, in this case, when only the lower-layer pixel electrodesPXM are formed as the pixel electrodes, the electric field generatedbetween the projections CP of the lower-layer pixel electrodes PXM andthe counter electrodes CT is surely controlled by an electric fieldwhich is substantially perpendicular to the transparent substrate SUB1at the most portion. This is because that with respect to an electricfield between a pair of electrodes which are arranged to close eachother in a plan view, by interposing the protective film PAS having arelatively thick film thickness, an electric field having componentssubstantially parallel to the transparent substrate SUB1 is decreasedand an electric field in the direction having components substantiallyperpendicular to the transparent substrate SUB1 is increased. In thiscase, the liquid crystal in use is activated in response to an electricfield having components substantially parallel to the transparentsubstrate SUB1 and hence, this implies that the mere provision ofprojections CP to the lower-layer pixel electrodes PXM cannot realizethe original task.

[0128] Accordingly, in this embodiment, also over the protective filmPAS, the upper-layer pixel electrodes PX having the normal pattern (apattern which has no projections corresponding to the projections CP)are formed in an overlapped manner on the lower-layer pixel electrodesPXM and, at the same time, out of the electric field generated in thevicinity of the bent portions between the upper-layer pixel electrodesPX and the counter electrodes CT, it is possible to ensure thecomponents of electric field substantially parallel to the transparentsubstrate SUB1 as much as possible.

[0129] Embodiment 2.

[0130]FIG. 2 is a plan view showing another embodiment of the pixel ofthe liquid crystal display device according to the present invention andcorresponds to FIG. 1A.

[0131] The constitution which makes this embodiment different from theembodiment shown in FIG. 1A lies in that the lower-layer counterelectrode CTM is also formed by way of an insulation film below thecounter electrode CT (excluding the counter electrode CT formed over thedrain signal line DL in an overlapped manner) which is arrangedsubstantially at the center of the pixel region. Accordingly, todiscriminate the counter electrode CT and the lower-layer counterelectrode CTM, the counter electrode CT may be also referred to as theupper-layer counter electrode CT.

[0132] The lower-layer counter electrode CTM has a center axis in therunning direction substantially aligned with a center axis of theupper-layer counter electrode CT and has a width thereof set smallerthan a width of the upper-layer counter electrode CT.

[0133] Further, the lower-layer counter electrode CTM is provided withprojections CP which are further projected from crests of convex-portionsides at respective bent portions. These projections CP are formed suchthat the projections CP are extended from the lower-layer counterelectrode CTM to an extent that the projections CP are sufficientlyprojected from the upper-layer counter electrode CT.

[0134] The respective lower-layer counter electrodes CTM having theprojections CP in this manner are formed on the same layer as thecounter voltage signal lines CL and are integrally formed with thecounter voltage signal lines CL.

[0135] Due to such a constitution, it is possible to decrease the domainwhich is generated between the counter electrode CT which is arrangedsubstantially at the center of the pixel region and the pixel electrodePX which is arranged close to the counter electrode CT.

[0136] Embodiment 3.

[0137]FIG. 3 is a plan view showing another embodiment of the pixel ofthe liquid crystal display device according to the present invention andcorresponds to FIG. 2.

[0138] The constitution which makes this embodiment different from theembodiment shown in FIG. 2 lies in that the lower-layer counterelectrodes CTM are formed close to the drain signal lines DL.Accordingly, due to the corresponding lower-layer counter electrodes CTMof other neighboring pixel regions in the x direction, the drain signallines DL are formed in a state that the drain signal line DL issandwiched between the lower-layer counter electrodes CTM.

[0139] Further, these lower-layer counter electrodes CTM are overlappedto the upper-layer counter electrodes CT which are formed over the drainsignal lines DL in an overlapped manner, whereby the lower-layer counterelectrodes CTM are formed such that they are not projected from theupper-layer counter electrodes CT.

[0140] Accordingly, since the drain signal line DL is arranged such thatthe drain signal line DL is surrounded by the counter electrodes CTM, CTto which the reference voltage is applied in three directions, it ispossible to have an advantageous effect that an electric field whichgenerates noises from the drain signal line DL can be substantiallycompletely blocked by shielding.

[0141] Further, in this embodiment, the lower-layer counter electrodeCTM which is arranged close to the drain signal line DL also includesthe projection CP which is further projected from the convex-portionside crest of each bent portion. The projection CP is formed such thatthe projection CP is extended from the lower-layer counter electrode CTMto an extent that the projection CP is sufficiently projected from theupper-layer counter electrode CT formed over the drain signal line DL inan overlapped manner.

[0142] The respective lower-layer counter electrodes CTM having theprojections CP in this manner are also formed on the same layer as thecounter voltage signal lines CL and are integrally formed with thecounter voltage signal lines CL.

[0143] Due to such a constitution, it is possible to further decreasethe domain which is generated between the counter electrode CT which isoverlapped to the drain signal line DL and the pixel electrode PX whichis arranged close to the counter electrode CT.

[0144] Embodiment 4.

[0145] For example, in both of the embodiment 2 and embodiment 3, thepixel electrode PX and the counter electrode CT have the two-layeredstructure interposing an insulation film and, at the same time, thelower pixel electrodes PXM and the lower-layer counter electrodes CTMare formed as different layers by way of an insulation film (insulationfilm GI).

[0146] However, it is possible to form the lower-layer pixel electrodePXM and the lower-layer counter electrode CTM on the same layer. In thiscase, when the projection CP of one electrode is formed in a furtherextended manner, there exists a possibility that one electrode iselectrically short-circuited with another electrode.

[0147] This embodiment is provided for overcoming such a drawback. Thatis, for example, FIG. 4A shows the bent portions and the vicinity of thepixel electrode PX and the counter electrode CT which is disposed closeto the pixel electrode PX.

[0148] The pixel electrode PX has a two-layered structure interposing aninsulation film between layers, wherein the pixel electrode PX isconstituted of the lower-layer pixel electrode PXM which is disposedbelow the insulation film and the upper-layer pixel electrode PXtdisposed above the insulation film. The counter electrode CT also has atwo-layered structure interposing the insulation film between layers,wherein the counter electrode CT is constituted of the lower-layercounter electrode CTM disposed below the insulation film and theupper-layer counter electrode CTt disposed above the insulation film.

[0149] The lower-layer pixel electrode PXM and the lower-layer counterelectrode CTM have projections CP which are further projected from theconvex-portion side crests of respective bent portions. Further, in theconcave portion of another electrode which faces the projection CT ofone electrode in an opposed manner, a notched portion DP is formed suchthat the notched portion DP further cuts off the concave portion ofanother electrode.

[0150] Due to such a constitution at this portion, corresponding to anamount of the notched portion DP formed in the bent portion of eachelectrode, the spaced-apart distance between respective electrodesbecomes large at this portion. Accordingly, even when the projectionportion CP of one electrode is further extended as shown in FIG. 4B, forexample, a drawback that the extension is electrically short-circuitedwith another electrode can be obviated.

[0151] Here, in FIG. 4B, a distal end portion of the projection CP ofthe lower-layer counter electrode CTM is configured to be overlapped tothe upper-layer pixel electrode PXt. Due to such a constitution, it hasbeen confirmed that it is further possible to have an advantageouseffect in suppression of the domain region and the enhancement of thenumerical aperture of the pixels.

[0152] Here, FIG. 5A, FIG. 5B, FIG. 5C are respectively cross-sectionalviews showing the distribution of an electric field generated betweenelectrodes when the distal end of the projection CP of the lower-layerelectrodes which constitutes one electrode approaches considerably tothe upper-layer electrode which constitutes another electrode or theseelectrodes are overlapped to each other.

[0153] Here, FIG. 5A shows a case in which between the projection CP ofthe lower-layer electrode which constitutes one electrode and theupper-layer electrode Tt which constitutes another electrode, theprotective film PAS which is made of organic material layer isinterposed. FIG. 5B shows a case in which between the projection CP ofthe lower-layer electrode which constitutes one electrode and theupper-layer electrode Tt which constitutes another electrode, asequential laminated body consisting of a protective film PAS1 formed ofan inorganic material layer and a protective film PAS2 formed of anorganic material layer is interposed. FIG. 5C shows a case in whichbetween the projection CP of the lower-layer electrode which constitutesone electrode and the upper-layer electrode Tt which constitutes anotherelectrode, an insulation film GI having a function of a gate insulationfilm of the thin film transistor TFT and a sequential laminated bodyconsisting of a protective film PAS1 formed of an inorganic materiallayer and a protective film PAS2 formed of an organic material layer areinterposed.

[0154] In these drawings, an electric field which is generated betweenthe projection CP of the lower-layer electrode which constitutes oneelectrode and the upper-layer electrode which constitutes anotherelectrode is referred to a so-called fringe electric field. In thelateral electric field type liquid crystal display device in which,respective electrodes are particularly formed of a light transmittingconductive body, this fringe electric field E can effectively activatethe liquid crystal.

[0155] Further, it is confirmed that along with the increase of thethickness of the insulation film such as the protective film or thelike, the density of the fringe electric field E is decreased. From thisphenomenon, it is effective to narrow a distance between the projectionCP of the lower-layer electrode which constitutes one electrode and theupper-layer electrode which constitutes another electrode in order ofFIG. 5A, FIG. 5B and FIG. 5C.

[0156] Further, although FIG. 4A and FIG. 4B show the constitution inwhich the notched portion DP is not formed in the electrode at a sidewhich faces the projection CP and constitutes the upper-layer electrode,it is needless to say that, as shown in the corresponding FIG. 6A andFIG. 6B respectively, a notched portion DP1 having the substantiallysame shape as the notched portion DP formed in the lower-layer electrodemay be formed in the upper-layer electrode PXt or CTt.

[0157] Embodiment 5.

[0158]FIG. 7 is a view which shows the more specific constitution of theprojection CP of one electrode T1 and the notched portion DP of anotherelectrode T2 at the bent portion with respect to one electrode T1 andanother electrode T2 which is disposed close to one electrode T1.

[0159] In this case, the rubbing direction RD of the orientation film isaligned in the y direction in the drawing, that is, in the runningdirection of the drain signal line DL.

[0160] In this case, by setting the relationship among inclinationangles (angles with respect to the y direction, θp1, θp2 in the drawing)of one electrode T1 and another electrode T2, an inclination angle (anangle with respect to the y direction, θj in the drawing) at one side ofthe projection CP of one electrode T1, an inclination angle (an anglewith respect to the y direction, θd in the drawing) at one side of theprojection CP of another electrode T2 as follows, it is confirmed thatthe further advantage is obtained with respect to the suppression ofdomain region and the enhancement of numerical aperture of the pixels.

[0161] That is, the relationship in which the inclination angles θp1,θp2 are set to a value not less than 5 degree and not more than 20degree, the inclination angle θj is set to a value not less than 30degree and not more than 90 degree, the inclination angle θd is set to avalue not less than 10 degree and not more than 60 degree, and θp1, θp2<θd≧θj is established.

[0162] Accordingly, the direction of the electric field from oneelectrode T1 to another electrode T2 does not exhibit an acute change inthe vicinity of the bent portion and hence, the occurrence of the domaincan be drastically decreased.

[0163] In such an electrode constitution, using the bent portion as aboundary, a liquid crystal director in regions close to both sides ofthe bent portion is increased at portions where the angle made by theliquid crystal director and the transmitting axis of the polarizer POL1assumes ±45°. That is, as described also in Japanese Unexamined patentPublication 160878/1994 (FIG. 7 in the publication), in the electrodeconstitution shown in FIG. 25, for example, with respect to a risingresponse speed Tr and a threshold voltage Vth (the lowest voltageapplied between the drive electrodes necessary for moving the liquidcrystal molecules) at an intermediate gray scale display of the liquidcrystal molecules LC1, LC2 present in a gap between parallel electrodeswhere the angles θp1 and θp2 are set to θp1=θp2=15°, for example, and anintermediate gray scale display of the liquid crystal molecules LC2, LC4present in a gap between electrodes where the angles θp1 and θp2 are setto θp1=θp2=45°, both properties are also improved as shown in FIG. 26 asan angle made by the driving electric field and the initial orientationdirection (rubbing direction RD) of the liquid crystal approaches 45°from 90° and hence, the liquid crystal director can be easily rotated.In FIG. 26, a place (corresponding to LC1, LC2, LC3, L4 shown in FIG.25) is taken on an axis of abscissas and a rising response speed Tr withrespect to the threshold voltage Vth is taken on an axis of ordinates.

[0164] Further, in such a constitution, even when a black display isperformed by shifting the driving electric field from an applied stateto a non-applied state, on both liquid crystal molecules which arerotatably driven in opposite directions from each other in the vicinityof the bent portion, a resilient force which makes the liquid crystalmolecules return to the original orientation state strongly acts andhence, the restoring force derived from the rubbing is added whereby theliquid crystal molecules are rotated faster so as to return to theoriginal orientation state. In this manner, the rising response speedcan be improved. In this manner, it is possible to improve theproperties of the liquid crystal molecules present in the gap betweenelectrodes in which the main lateral-direction driving electric field isgenerated and, at the same time, the domain generating region can beformed in a stable manner in manufacturing and hence, the luminance inthe vicinity of the bent portion can be made stable.

[0165] According to the electrode constitution of this embodiment, dueto the provision of the notched portion DP, even when the drivingelectrode which faces the conductive layer in an opposed manner isformed on the same layer, a drawback such as the electricshort-circuiting can be eliminated. Accordingly, as shown in FIG. 27,for example, some pixel electrodes PX and some counter electrodes CT maybe formed of only a transmitting conductive layer above the protectivefilm PAS. Here, FIG. 27 corresponds to FIG. 1. A position of a portion Ain FIG. 27 corresponds to the portion shown in FIG. 7 or FIG. 25.

[0166] However, it is needless to say that this embodiment is applicableto a case in which all of the pixel electrodes PX and the counterelectrodes CT in the pixel region are respectively formed of one layer.

[0167] Further, in the same manner as the constitution on the embodiment4, when the pixel electrodes PX and the counter electrodes CT arerespectively realized by the two-layered structure by way of theinsulation layer, it is needless to say that it is sufficient that aperiphery of an envelope pattern of two-layered conductive electrodes asviewed in plan satisfies the above-mentioned constitution.

[0168] Embodiment 6.

[0169]FIG. 8 is a plan view showing another embodiment of the pixels ofthe liquid crystal display device according to the present invention.The drawing shows the detail of the thin film transistor TFT and thevicinity thereof.

[0170] In the drawing, the characteristic constitution of thisembodiment lies in that the drain signal lines DL which are formed in azigzag shape as a result of adopting the so-called multi-domain systemare arranged such that the gate signal line GL crosses the bent portionof the drain signal line DL and, at the same time, the thin filmtransistor TFT is arranged over the gate signal line GL at theconcave-portion side of the bent portion of the drain signal line DL.

[0171] Further, the drain electrode SD1 of the thin film transistor TFTis constituted of a portion of the drain signal line DL, while thesource electrode SD2 which constitutes a pair with the drain electrodeSD1 is arranged to face the drain electrode SD1 in an opposed manneralong the running direction of the gate signal line GL. In other words,a channel length of the thin film transistor TFT is formed such that itis arranged parallel to the running direction of the gate signal linesGL.

[0172] Accordingly, the portion of the drain signal line DL whichfunctions as the drain electrode SD1 (portion of the bent portion) isprocessed such that the portion is arranged parallel in the y directionat the side which faces the source electrode SD2 in an opposed mannerand, at the same time, the side of the source electrode SD2 at the drainsignal line DL side is formed in parallel to the y direction.

[0173] Here, the thin film transistor TFT is positioned within theextensions of the drain signal line DL and the pixel electrode PX closeto the drain signal line DL and is set such that assuming the width ofthe drain electrode SD1 as N_(D), the channel length as L and the widthof the source electrode SD2 as W_(S), the relationship P>N_(D)+L+W_(S)is established. Here, P indicates the distance between outer sides ofthe drain signal line DL and the pixel electrode PX.

[0174] The pixel having such a constitution can, first of all,effectively prevent the domain which is liable to easily occur in thevicinity of the gate signal line GL. At the same time, the pattern ofthe source electrode SD2 of the thin film transistor TFT and thevicinity portion of the pixel electrode PX which is connected to thesource electrode SD2 can be simplified. Further, it is possible toprevent the short-circuiting of the pixel electrode PX with otherelectrode with high probability.

[0175] That is, in the drawing, the occurrence of the domain in thepixel region at the left side in the drawing with respect to the pixelelectrode PX is obviated using the counter voltage signal line CLt,while the occurrence of the domain in the pixel region at the right sidein the drawing is obviated using the extension J1 of the pixel electrodePX.

[0176] In this case, the extension J1 of the pixel electrode PX can makethe region defined between the pixel electrode PX and the sourceelectrode SD2 extend to the center side of the pixel region whereby theoccurrence of domain can be suppressed. It is needless to say that ageometric shape of the extension J1 of the pixel electrode PX is setsuch that the direction of the electric field generated between theextension J1 and the counter electrode CT arranged close to theextension J1 is defined without being largely different from thedirection of the normal electric field.

[0177] This implies that in the vicinity of the thin film transistor TFTwhere the respective members are arranged in a relatively complicatedmanner, the pattern of the pixel electrode PX in the vicinity of thesource electrode SD2 can be simplified and hence, the fear of occurrenceof short-circuiting between the pixel electrode PX with other conductivelayer on the same layer can be eliminated.

[0178] Here, the geometric shape of the counter voltage signal line CLtfor obviating the occurrence of domain in the pixel region at the leftside of the drawing with respect to the pixel electrode, since thecounter voltage signal line CLt is formed on the protective film PAS,also provides a spatial margin and hence, it gives rise to no seriousproblem compared to the pattern of the pixel electrode PX in thevicinity of the source electrode SD2. Further, as shown in FIG. 8,places where the through holes TH which connect the source electrode SD2and the upper-layer pixel electrode PXt are formed can be arrangedbetween the extension J1 and the gate signal line GL and hence, it ispossible to solve the drawback that the numerical aperture is lowereddue to the occurrence of domain in the vicinity of these places.

[0179] Here, FIG. 9 is an explanatory view which is drawn by taking acase in which the thin film transistor TFT is formed on theconvex-portion side of the bent portion of the drain signal line DL intoconsideration. Here, FIG. 9 is depicted such that the position of thethin film transistor TFT is changed using the constitution of the drainsignal line DL and the pixel electrode PX shown in FIG. 8 as thereference.

[0180] Accordingly, in FIG. 9, in the same manner as FIG. 8, theoccurrence of domain can be obviated by the counter voltage signal lineCL at the left-side pixel region in the drawing with respect to thepixel electrode PX, while the occurrence of domain can be obviated bythe extension J1 of the pixel electrode PX at the right-side pixelregion in the drawing.

[0181] As can be clearly understood from FIG. 9, the extension J1 of thepixel electrode PX for obviating the domain at the right-side pixelregion in the drawing with respect to the pixel electrode PX must beextended to an extent such that the extension J1 is arranged close tothe right-side drain signal line DL and hence, the extension J1 must bearranged close to the gate signal line GL.

[0182] It is needless to say that the geometric shape of the extensionJ1 in this case is determined on the premise that the direction of theelectric field generated between the extension J1 and the counterelectrode CT which is arranged close to the extension J1 is set withoutbeing largely different from the direction of the normal electric field.

[0183] Here, the geometric shape of the counter voltage signal line CLtfor obviating the occurrence of domain at the left-side pixel region inthe drawing with respect to the pixel electrode PX is substantiallyequal to the geometric shape shown in FIG. 8.

[0184] Further, by adopting the constitution shown in FIG. 8, it is alsopossible to enhance the so-called numerical aperture of the pixelsimultaneously.

[0185] That is, FIG. 10A is an explanatory view showing the pixel regiondefined between the pixel electrode PX which is connected to the sourceelectrode SD2 of the thin film transistor TFT and the drain signal lineDL which is connected to the drain electrode SD1 of the thin filmtransistor TFT.

[0186] Due to the presence of the extension J1 in the vicinity of theconnection portion between the pixel electrode PX and the sourceelectrode SD2, electric field noises e (indicated by bold-line arrows inthe drawing) from the gate signal line GL can hardly intrude the pixelregion. That is, the extension J1 is formed such that the extension J1extends to an extent that the extension J1 is arranged substantiallyclose to the counter electrode CT which is overlapped to the drainsignal line DL, whereby an intrusion path of the electric field noises eis narrowed.

[0187] Here, FIG. 10B shows a case in which the thin film transistor TFTis arranged at the convex-portion side of the bent portion of the drainsignal line DL. That is, FIG. 10B is an explanatory view which shows thepixel region defined between the pixel electrode PX which is connectedto the source electrode SD2 of the thin film transistor TFT and thedrain signal line DL which is connected to the drain electrode SD1 ofthe thin film transistor TFT.

[0188] Although, as mentioned previously, the occurrence of domain inthe pixel region at such a portion is obviated by the counter voltagesignal line CLt which sufficiently covers the gate signal line GL, toeffectively prevent the electric field noises e from the gate signalline GL, it is necessary to relatively largely increase a width of thecounter voltage signal line CLt at this portion.

[0189] This is because a thickness of the protective film PAS on whichthe counter voltage signal line CLt is formed is relatively large andhence, to effectively obviate the electric field noises e from the gatesignal line GL, it is necessary to increase the width of the countervoltage signal line CLt correspondingly.

[0190] In this manner, it is possible to obtain the above-mentionedrespective advantageous effects by arranging the thin film transistorTFT to the concave-portion side of the bent portion of the drain signalline DL. Accordingly, in this embodiment, by forming the bent portion ofthe drain signal line DL also substantially at the center portion of thepixel region, it is possible to form the bent portion having the concaveportion in the same direction at the portion where each drain signalline DL crosses the gate signal line GL.

[0191] Accordingly, it is possible to arrange the thin film transistorsTFT at the same corresponding places in respective pixels.

[0192] Embodiment 7.

[0193]FIG. 11 is a plan view showing another embodiment of the pixel ofthe liquid crystal display device according to the present invention andcorresponds to FIG. 8.

[0194] The constitution which makes this embodiment different from theembodiment shown in FIG. 8 lies in the constitution of the drainelectrode SD1 and the source electrode SD2 of the thin film transistorTFT.

[0195] First feature lies in that with respect to the drain electrodeSD1, a portion of the drain signal line DL is used as the drainelectrode of the thin film transistor TFT in its original form.

[0196] That is, the drain signal line DL is formed in a “L-shaped”pattern having the bent portions at portions thereof where the drainsignal line DL crosses the gate signal line GL. These bent portions andthe vicinity thereof are used as the drain electrodes SD1 withoutprocessing them at all. However, the vicinity CNT of the center portionof the bent portion is partially arranged in parallel in the y directionto set the channel length L to a fixed value.

[0197] On the other hand, the source electrode SD2 of the thin filmtransistor TFT is formed such that the side of the source electrode SD2which faces the drain electrode SD1 is formed in a shape which is formedby shifting the side of the drain electrode SD1 which faces the sourceelectrode SD2 in the x direction.

[0198] Due to such a constitution, the channel region between the drainelectrode SD1 and the source electrode SD2 is formed in an “L-shaped”pattern having bent portions so that the channel width can be increased.

[0199] Further, when the thin film transistor TFT is arranged at theconcave-portion side of the bent portion of the drain signal line DL andthe channel region is formed in an “L shape”, the directions of electriccurrents which flow inside the channel region are directed in thedirection that the electric currents are converged to each other asshown in FIG. 12A. This implies that an area of the source electrode SD2which is overlapped to the gate signal line GL can be reduced.

[0200] Accordingly, this embodiment gives rise to an advantageous effectthat the capacitance Cgs between the gate electrode SD1 and the sourceelectrode SD2 of the thin film transistor TFT can be reduced.

[0201] On the other hand, in FIG. 12B, a case in which the thin filmtransistor TFT is arranged at the convex-portion side of the bentportion of the drain signal line DL is taken into consideration. In thiscase, the directions of electric currents which flow inside the channelregion of the thin film transistor TFT are directed in the directionthat the electric currents are diffused. As a result, it is necessary toincrease the source electrode SD2 so that there is no other way but toincrease the capacitance Cgs.

[0202] Further, as described above, in the vicinity of the sourceelectrode SD2 of the thin film transistor TFT of the pixel electrode PX,it is necessary to form the extension which blocks the electric fieldnoises from the gate signal lines GL by shielding and hence, the statein which the capacitance Cgs between the extension and the gate signalline GL is further added.

[0203] Here, in FIG. 12A and FIG. 12B, ΔCgs·off, ΔCgs·on respectivelyindicate a region to which the capacitance Cgs which is generated whenthe thin film transistor TFT is switched off contributes and a region towhich the capacitance Cgs which is generated when the thin filmtransistor TFT is switched on contributes.

[0204] Embodiment 8.

[0205]FIG. 13 is a plan view showing another embodiment of the liquidcrystal display device according to the present invention. Further, FIG.14 is a cross-sectional view taken along a line XIV-XIV in FIG. 13.

[0206]FIG. 13 shows the drain signal line DL, the counter electrodes CTMwhich are arranged at both sides of the drain signal line DL and thecounter electrode CT which is formed of a light-transmitting conductivelayer which is arranged in an overlapped manner with the drain signalline DL and the counter electrodes CTM.

[0207] Due to such a constitution, as shown in FIG. 14, it is possibleto provide the constitution in which the electric field (electric fieldnoises e) from the drain signal line DL is terminated to the counterelectrodes CT which are arranged at both sides of the drain signal lineDL and the counter electrode CT which is formed above the drain signalline DL, while the electric field (electric field noises e) is notterminated to the pixel electrode PX arranged close to the drain signalline DL.

[0208] Further, according this embodiment, the drain signal line DL andthe counter electrodes CTM which are arranged at both sides of the drainsignal line DL are formed at different layers by way of the insulationfilm and, at the same time, the respective counter electrodes CTM whichare arranged at both sides of the drain signal line DL are electricallyconnected to each other by connectors SH which cross the drain signalline DL at a given interval in the running direction thereof thusforming a so-called ladder-like pattern.

[0209] Respective widths Wm of the counter electrodes CTM aresubstantially determined based on the width WD of the drain signal lineDL and the width WIT of the counter electrode CT and are usuallynarrower than the widths of other electrodes.

[0210] Accordingly, to prevent the disconnection of the counterelectrodes CTM, the counter electrodes CTM are formed in the ladderpattern. Accordingly, even when one counter electrode CTM isdisconnected, the signal can be supplied to a distal terminal of onecounter electrode CTM through one of connectors which are formed withthe disconnected portion interposed therebetween, the other counterelectrode CTM and another connector. Due to such a constitution, it iseffective to arrange the above-mentioned connectors SH with a relativelynarrow distance between the connector SH and the neighboring anotherconnector SH.

[0211] Here, although the connector SH has also a function of supplyingthe reference signal to the counter electrode CT of the neighboringpixel region, the connector SH is mainly constituted to solve thedrawback attributed to the disconnection of the counter electrode CTM.This is because the counter electrode CTM is configured to have at leastone end thereof connected to the counter voltage signal line CL forsupplying the reference signal to the counter electrode CT of theneighboring pixel region.

[0212] Embodiment 9.

[0213]FIG. 15 is a plan view showing one embodiment when theabove-mentioned respective embodiments are applied to the pixel regionof the liquid crystal display device. Further, FIG. 16A is across-sectional view taken along a line XVIA-XVIA in FIG. 15 and FIG.16B is a cross-sectional view taken along a line XVIB-XVIB in FIG. 15.

[0214] In this embodiment, one pixel includes one pixel electrode PX andtwo counter electrodes CT respectively arranged at the both sides of thepixel electrode PX. The lower-layer pixel electrode PXM is arrangedbelow the pixel electrode PX and the lower-layer counter electrodes CTMare arranged below the counter electrodes CT. The lower-layer counterelectrodes CTM are formed at both sides of the drain signal line DL onthe layer different from the layer of the drain signal line DL by way ofan insulation film. Further, the lower-layer counter electrodes CTM haveportions thereof connected with each other by means of the connectionportions SH which are arranged to cross the drain signal line DL.

[0215] Further, the drain signal line DL has a zigzag shape having bentportions at portions where the drain signal lines DL cross the gatesignal lines GL and the approximately center of the pixel region. A thinfilm transistor TFT which is arranged on the gate signal line GL isarranged close to the concave-portion side of the bent portion of thedrain signal line DL.

[0216] Further, in FIG. 15, members indicated by SOC are so-calledcolumnar spacers. As shown in FIG. 16B, the columnar spacers SOC arespacers which are made of resin, for example, and are formed on theliquid-crystal-side surface of the transparent substrate SUB2. Due tothese columnar spacers, a layer thickness of the liquid crystal ismaintained uniform.

[0217] This columnar spacers SOC are formed on an upper surface of theblack matrix BM and a leveling film OC which are sequentially formed onthe surface of the transparent substrate SUB2.

[0218] The respective steps of one embodiment of the manufacturingmethod of the liquid crystal display device having such a constitutionare explained hereinafter in conjunction with FIG. 17 to FIG. 23. Here,a photolithography method is performed once in each step shown in eachdrawing and hence, the pixel regions of the transparent substrate SUB1side can be formed by performing the photolithography method seven timesin total.

[0219] Step 1. (FIG. 17)

[0220] First, the gate signal lines GL are formed on the liquidcrystal-side surface of the transparent substrate SUB1. As the materialof this gate signal line GL, for example, a laminated body which isformed by laminating a Mo—Cr layer or a Mo—Zr layer having a thicknessof approximately 60 nm to the Al—Nd layer having a thickness ofapproximately 250 nm is used.

[0221] In addition, it is needless to say that the gate signal line GLmay have a so-called anodized film formed on the surface thereof.

[0222] Thereafter, an insulation film GI is formed over the transparentsubstrate SUB1 such that the insulation film GI also cover the gatesignal line GL. This insulation film GI becomes a gate insulation filmof the thin film transistor TFT and hence, a film thickness of theinsulation film GI is set to have the function as a gate insulationfilm. As the material of the insulation film GI, for example, a siliconnitride film (SiN) having a thickness of approximately 350 nm is used.

[0223] Further, an amorphous silicon (a-Si) layer AS having a thicknessof approximately 200 nm is formed on a surface of the insulation film GIand a highly concentrated N⁺ impurity layer is formed on a surface ofthe amorphous silicon layer AS by doping the surface with phosphorous.

[0224] In addition, by sequentially forming the insulation film GI andthe amorphous silicon (a-Si) layer AS collectively using a same bell jarby a CVD method, for example, the step can be performed reliably whilepreventing the intrusion of impurities.

[0225] Step 2 (FIG. 18)

[0226] Then, the amorphous silicon layer AS is formed in a givenpattern. Here, the amorphous silicon layer AS is made to remain not onlyin the region for forming the thin film transistor TFT but also in theregion for forming the pixel electrode PX. This provision is forpreventing breaking of the pixel electrode PX which is formed later dueto a stepped portion.

[0227] Step 3. (FIG. 19)

[0228] Next, the counter voltage signal lines CL, the counter electrodesCTM connected to the counter voltage signal lines CL, the drainelectrodes SD1 and the source electrodes SD2 of the thin transistors TFTare formed. As the materials of the counter voltage signal lines CL, thecounter electrodes CT, the drain electrodes SD1 and the sourceelectrodes SD2, for example, any one of Mo—Cr, Mo—Zr, Ta, Ti, Cr and thelike can be used. With regard to the film thickness of the countervoltage signal line CL, the counter electrode CT, the drain electrodeSD1 and the source electrode SD2, it is appropriate to set the filmthickness to about 120 nm.

[0229] Using the drain electrode SD1 and the source electrode SD2 of thethin film transistor TFT as masks, the N-type impurity layer on an uppersurface of the amorphous silicon layer AS which is exposed from themasks is removed by etching.

[0230] Then, the protective film PAS1 is formed on a surface of thetransparent substrate SUB1 such that the protective film PAS1 alsocovers the counter voltage signal lines CL and the counter electrodesCTM. As the material of the protective film PAS1, a silicon nitride film(SiN) is used, for example, and the appropriate film thickness is about200 nm.

[0231] Step 4. (FIG. 20)

[0232] Through holes TH are formed in the protective film PAS1 and, viathese through holes TH, portions of the drain electrodes SD1 andportions of the source electrodes SD2 of the thin film transistors TFTare exposed.

[0233] It is preferable that these through holes TH are formed by dryetching. In this case, it is also preferable to form the through holesat the terminal portions of the gate signal lines GL and the drainsignal lines DL simultaneously.

[0234] Step 5 (FIG. 21)

[0235] Next, the drain signal lines DL, the lower-layer pixel electrodesPXM and the conductive layers are formed. Here, the conductive layersare formed on portions which face the columnar spacers.

[0236] As the material of the drain signal lines DL, the lower-layerpixel electrodes PXM and the conductive layers, a laminated body whichis formed by sequentially laminating, for example, a Mo—Cr layer or aMo—Zr layer having a thickness of approximately 60 nm, an Al—Nd layerhaving a thickness of approximately 250 nm, a Mo—Cr layer or a Mo—Zrlayer having a thickness of approximately 60 nm is used.

[0237] Step 6 (FIG. 22)

[0238] The protective film PAS2 is formed. This protective film PAS2 isconstituted of an organic material layer and is preferably formed by acoating method. The appropriate thickness of the protective film pAS2 isabout 2000 nm. Then, by forming through holes TH in the protective filmPAS2, portions of the extensions of the portions of the pixel electrodesPXM which are connected to the source electrodes SD2 of the thin filmtransistors TFT are exposed.

[0239] Step 7. (FIG. 23)

[0240] On the surface of the protective film PAS2, the counterelectrodes CT, the counter voltage signal lines CLt and the upper-layerpixel electrodes PX are formed. As the material of the counterelectrodes CT, the counter voltage signal lines CLt and the upper-layerpixel electrodes PX, for example, a conductive layer having nonlight-transmitting property such as ITO (Indium Tin Oxide), ITZO (IndiumTin Zinc Oxide) or the like is used.

[0241] Embodiment 10.

[0242]FIG. 28 is a plan view showing another embodiment of the pixel ofthe liquid crystal display device according to the present invention andcorresponds to FIG. 21, for example.

[0243] In this embodiment, when a short-circuited portion (for example,indicated by a T portion in the drawing) is formed between the counterelectrode CTM and the drain signal line DL which is formed over thecounter electrode CTM by way of the insulation layer, it is possible torepair the short-circuited portion using laser beams such that thedisplay is not influenced. That is, portions of the conductive layer ofthe counter electrode CTM are arranged in the vicinity of the gatesignal lines thus forming portions which are not overlapped to the drainsignal lines and these portions C1, C2, C3, C4 are cut.

[0244] Further, when a portion where the drain signal line DL isdisconnected (for example, indicated as a portion K in the drawing), theportions C1, C2, C3, C4 are cut by the laser beams and, thereafter, thelaser beams are radiated to the short-circuited portions S1, S2, wherebythe drain signal line DL is electrically connected to the portion whichwas the pattern of the counter electrode CTM.

[0245] Embodiment 11.

[0246]FIG. 29 is a plan view showing another embodiment of the pixel ofa liquid crystal display device according to the present invention andshows the constitution of color filters FIL formed on theliquid-crystal-side surface of the transparent substrate SUB2.

[0247] In the drawing, the black matrix BM has a pattern extending alongthe gate signal line GL and each color filter FIL is formed having bentportions in an L shape along the drain signal line DL. In conformitywith the shape of the bent portions of the drain signal line DL, also onthe bent portions of the above-mentioned color filter FIL, theprojections CPF which are further projected from the convex-portion-sidecrests of the bent portions are formed. Alternatively, the notchedportions DPF may be formed in the concave-portion side of the bentportion.

[0248] Due to such a constitution, leaking of light can be eliminatedand a desired liquid crystal gap can be obtained.

[0249] The above-mentioned respective embodiments can be usedindividually or in combination. This is because the advantageous effectof the respective embodiments can be performed individually or in acombined form.

[0250] As can be clearly understood from the above explanation, theliquid crystal display device according to the present invention canimprove the numerical aperture, can suppress the generation of thedomain and can improve the display quality.

What is claimed is:
 1. A liquid crystal display device beingcharacterized in that on each pixel region formed on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, a pixel electrode having a bentportion and a counter electrode which is arranged at a position wherethe pixel electrode is shifted in parallel are formed, at least oneelectrode out of the pixel electrode and the counter electrode isconstituted of two electrodes which are superposed as an upper layer anda lower layer by way of an insulation film, and a projection which isfurther projected from a crest of a convex-portion side of the bentportion toward another electrode side is formed on the lower-layer-sideelectrode out of two electrodes.
 2. A liquid crystal display deviceaccording to claim 1, wherein in the lower-layer-side electrode ofanother electrode, a notched portion which further cuts off a bottomportion of a concave-portion side of the bent portion is formed.
 3. Aliquid crystal display device according to claim 1, wherein aninsulation film interposed between two pixel electrodes and aninsulation film interposed between two counter electrodes differ in thenumber of lamination.
 4. A liquid crystal display device beingcharacterized in that on a liquid-crystal-side surface of one substrateout of respective substrates which are arranged to face each other in anopposed manner with liquid crystal therebetween, regions which aresurrounded by a plurality of juxtaposed gate signal lines and aplurality of juxtaposed drain signal lines which cross the gate signallines are formed as pixel regions, a thin film transistor driven inresponse to a scanning signal from the gate signal line and a pixelelectrode to which a scanning signal is supplied from the drain signalline through a drain electrode and a source electrode of the thin filmtransistor are provided to the inside of each pixel region, the drainsignal line is formed in a zigzag shape having a bent portion at aportion where a drain signal line crosses the gate signal line and atleast at a substantially center portion of the pixel region, the thinfilm transistor is formed in the vicinity of the concave-portion side ofthe bent portion of the drain signal line, the drain electrode is formedof a portion of the drain signal line, and the source electrode isformed so as to face the drain electrode in an opposed manner with achannel length in the running direction of the gate signal line.
 5. Aliquid crystal display device according to claim 4, wherein the sourceelectrode of the thin film transistor is connected to the pixelelectrode, and the vicinity of the connecting portion of the pixelelectrode with the source electrode includes an extension having apattern which reduces a domain between the pixel electrode and thecounter electrode and blocks electric field noises from the gate signalline by shielding.
 6. A liquid crystal display device according to claim4, wherein the thin film transistor is arranged between extensions ofthe pixel electrode and the counter electrode which are arranged closeto each other.
 7. A liquid crystal display device being characterized inthat on a liquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal therebetween, regions which are surrounded by aplurality of juxtaposed gate signal lines and a plurality of juxtaposeddrain signal lines which cross these gate signal lines are formed aspixel regions, a thin film transistor driven in response to a scanningsignal from the gate signal line and a pixel electrode to which ascanning signal is supplied from the drain signal line through a drainelectrode and a source electrode of the thin film transistor areprovided to the inside of each pixel region, the drain signal line isformed in a zigzag shape having a bent portion at a portion where adrain signal line crosses the gate signal line and at least at asubstantially center portion of the pixel region, the thin filmtransistor is formed in a pattern in which a side of the drain electrodewhich faces the source electrode in an opposed manner has a concaveportion and also in a pattern in which a side of the source electrodewhich faces the drain electrode in an opposed manner has a convexportion.
 8. A liquid crystal display device according to claim 7,wherein the drain electrode of the thin film transistor uses the patternof the bent portion of the drain signal line as it is.
 9. A liquidcrystal display device being characterized in that on aliquid-crystal-side surface of one substrate out of respectivesubstrates which are arranged to face each other in an opposed mannerwith liquid crystal there between, pixel regions which are surrounded bya plurality of juxtaposed gate signal lines and a plurality ofjuxtaposed drain signal lines which cross these gate signal lines areformed, on each pixel region, a switching element which is driven inresponse to a scanning signal from the gate signal line, a pixelelectrode to which a video signal is supplied from the drain signal linethrough the switching element, and a counter electrode which isconnected to a counter voltage signal line and generates an electricfield between the pixel electrode and the counter electrode are formed,the counter electrode includes a lower-layer counter electrode and anupper-layer counter electrode which is formed above the lower-layercounter electrode, the lower-layer counter electrode is formed such thatthe lower-layer counter electrodes are respectively arranged at bothsides of the drain signal line through the drain signal line and a firstinsulation film, and the upper-layer counter electrode is formed suchthat the upper-layer counter electrode covers the drain signal line andthe lower-layer counter electrodes byway of a second insulation film.10. A liquid crystal display device according to claim 9, wherein thedrain signal line and the lower-layer counter electrodes which arearranged at both sides of the drain signal line have bent portions and,at the same time, projections which are further projected from crests atconvex-portion sides of the bent portions of the lower-layer counterelectrodes and are extended to the pixel electrode side are formed. 11.A liquid crystal display device being characterized in that on eachpixel region formed on a liquid-crystals-side surface of one substrateout of respective substrates which are arranged to face each other in anopposed manner with liquid crystal therebetween, a pixel electrodehaving a bent portion and a counter electrode which is arranged at aposition where the pixel electrode is shifted in parallel, and aprojection which is projected from a crest of the convex-portion side ofthe bent portion of one electrode out of the pixel electrode and thecounter electrode toward a bottom portion of the concave-portion side ofthe bent portion of another electrode which faces one electrode isformed, and the bottom portion of the concave-portion side of the bentportion of the another electrode is notched to form a notched portion.12. A liquid crystal display device according to claim 9, wherein therespective lower-layer counter electrodes which are arranged at bothsides of the drain signal line are connected to each other by connectorswhich are arranged to cross the drain signal line.
 13. A liquid crystaldisplay device according to claim 9, wherein the lower-layer counterelectrodes are bent away from each other such that the lower-layercounter electrodes are not overlapped to the drain signal line at a sideof the gate signal line.
 14. A liquid crystal display device beingcharacterized in that on a liquid-crystal-side surface of one substrateout of respective substrates which are arranged to face each other in anopposed manner with liquid crystal therebetween, pixel regions which aresurrounded by a plurality of juxtaposed gate signal lines and aplurality of juxtaposed drain signal lines which cross these gate signallines are formed, on each pixel region, a switching element which isdriven in response to a scanning signal from the gate signal line, apixel electrode to which a video signal is supplied from the drainsignal line through the switching element, and a counter electrode whichis connected to a counter voltage signal line and generates an electricfield between the pixel electrode and the counter electrode are formed,the counter electrode includes a lower-layer counter electrode and anupper-layer counter electrode which is formed above the lower-layercounter electrode, the lower-layer counter electrode is formed such thatthe lower-layer counter electrode is constituted of an intermediateconductive layer between the drain signal line and the gate signal line,is insulated from the drain signal line by way of a first insulationfilm and is insulated from the gate signal line by way of a thirdinsulation film, is arranged in the vicinity of at least one signal lineout of the drain signal line and the gate signal line, and is extendedin the extending direction of the drain signal line.
 15. A liquidcrystal display device according to claim 14, wherein the lower-layercounter electrode constitutes an overlapped region together with thepixel electrode by way of the first insulation film and forms a holdingcapacitance in the region.
 16. A liquid crystal display device accordingto claim 14, the upper-layer counter electrode and lower-layer counterelectrode are electrically connected to each other over the gate signalline within the pixel region via a through hole.
 17. A liquid crystaldisplay device being characterized in that on a liquid-crystal-sidesurface of one substrate out of respective substrates which are arrangedto face each other in an opposed manner with liquid crystaltherebetween, pixel regions which are surrounded by a plurality ofjuxtaposed gate signal lines and a plurality of juxtaposed drain signallines which cross these gate signal lines are formed, on anothersubstrate, color filters having bent portions are formed within thepixel region, and projections which are further projected from crests ofconvex-portion sides of the bent portions are formed or notched portionsare formed at the concave-portion sides of the bent portions.